1. Technical Field
The present invention generally relates to the field of sophorolipids having anti-fungal properties and more specifically relates to methods for using such sophorolipids as anti-fungal agents. The invention also relates to 17-L-[(2′-O-β-D-glucopyranosyl-β-D-glucopyranosyl)-oxy]-cis-9-octadecenoate based sophorolipids and their uses as anti-fungal agents.
2. Prior Art
First described in 1961, sophorolipids occurs as a mixture of macrolactone and free acid structures that are acetylated to various extents at the primary hydroxyl position of the sophorose ring. Gorin, P. A. et al., Can. J. Chem., vol. 39, p. 846 (1961). Careful examinations have revealed that at least eight structurally different sophorolipids are produced. Davila, A. M. et al., J. Chromatogr., vol. 648, p. 139 (1993). The main component of sophorolipids is 17-hydroxyoctadecanoic acid and its corresponding lactone. Tulloch, A. P. et al., Can. J. Chem., vol. 40, p. 1326 (1962) and Tulloch, A. P. et al., Can J. Chem., vol. 46, p. 3337 (1968).
Work has been carried out to tailor sophorolipid structure during in vivo formation, mainly by the selective feeding of different lipophilic substrates. Zhou, Q.-H., et al., J. Am. Oil Chem. Soc., vol. 72, p. 67 (1995). Also unsaturated C-18 fatty acids of oleic acid may be transferred unchanged into sophorolipids. Rau, U. et al., Biotechnol. Lett., vol. 18, p. 149 (1996). However, while physiological variables during fermentation have provided routes to the variation of sophorolipid composition, this has not led to well-defined pure compounds.
Existing data suggests that glycolipids may be useful in treating very severe immune disorders. For example, glycolipids have been reported to be of interest for in vivo cancer treatment/antitumor cell activity, treatment of autoimmune disorders, in vivo and in vitro anti-endotoxic (septic) shock activity, regulation of angiogenesis, and apoptosis induction, all by cytokine activity. See, e.g., U.S. Pat. No. 5,597,573 to Massey, U.S. Pat. No. 5,514,661 to Piljac, U.S. Pat. No. 5,648,343 to Carlson, and the references cited in notes 9-13 of Bisht, K. S. et al., J. Org. Chem., vol. 64, pp. 780-789 (1999).
Thus, there exists a need to develop new and improved treatments for various human disorders using glycolipids. It is to the development of sophorolipids for these treatments, for other pharmaceutical and industrial purposes, and for other purposes, that the present invention is directed.